Pencil



F. R. BARKER Jan. 7, 1936.

PENCIL Filed July 26, 1935 llllflvllllf I .l lllflrldllll. Il

Patented Jan. 7, 1936 UNITED STATES' PATENT OFFICE 24 Claims.

This invention relates to a writing device of the type having aself-feeding writing element, and its principal object is to provide a pencil wherein, as the writing element or lead wears down to a given readily writable but not easily breakable distance'of exposed lead, the feeding mechanism. becomes automatically operative to maintain the lead approximately at said distance.

Another object lof the invention is to provide a mechanismwhich is of very simple yet readily accessible construction and which is reliable in its automatic operation but is capable of manual operation in case of failure of said automaticity.

Another object of the invention is to allow the use of a special shape of lead which', as the pencil is periodically rolled in the hand while writing, gives a very much finer writing point than leads now in common use.

Further objects of the invention relate to the construction and operation of my pencil and will be apparentffrom a consideration of the following description and accompanying drawing.

In the drawing Figure 1 is a broken longitudinal section.

Figure 2 is a section on line 2--2 of Figure l.

Figure 3 is a section on line 3 3 of Figure 1.

Figure 4 is a section on line 4-4 of Figure 1; and

Fig. 5 isa fragmentary longitudinal sectional view showing the lrelative positions of the control member and writing element during the writing Y operation.

The pencil herein shown for the purpose of illustration comprises an elongate, generally hexagonal body having an outer casing I tapered at the lower end to receive the ferrule tip 2. The casing I has an axial bore 3 down as far as the beginning of the casing taper. Contiguous with vthis bore 3 in the casing are the grooves 4 for holding extra leads. commencing at the bottom end of the bore 3 and running down into the taper of the casing for the distance shown is the smaller bore 5.

Fitting loosely in, and resting on, the bottom of the bore 5 is a tubular runner guide 6 split for its whole length by the slot 1 (Fig. 2). At a distance up equal to the length of the -bore 5 there is pressed out from this runner guide 6 a lug B which fits' into one of the grooves 4 and thus keeps the runner guide from turning in the casing I.

vWith an easy running llt in this tubular runner guide 6 is the tubular feed screw 9 having a left (Cl. 1Z0-18) hand screw groove. Fitting loosely inside this tubular feed screw 9 is the tubular runner I0 having on it a tit ll-which extends thru the feed screw 9 into the runner guide slot 1. Fitting loosely inside this tubular runner I0 is the tubular lead pusher I2 having on it a tit I3 which extends thru the runner Ill and then on thru the feed screw 9 into the runner guide slot 'l at a distance from the tit II (in the position shown) ,equal to the lead cf the screw plus half the width of the feed screw groove, the tits II and I3 being of a. size approximately half the width of the feed screw groove.

Into the upper end of the tubular feed screw 9 is iixedly fitted the tubular check seat I4 the' top of which is pressed over to form an outward flange, which abuts a thrust washer I5. With the Vwasher Il as a seat the spring I8 presses the check I1 against the seat of the check seat I4, the lower end of check Il being freely guided in said check seat I4. Into an axial hole in the lower end of this checlr- Il is securely fastened the upper end oi' the control rod I8 which extends down thru the pencil to a given distance beyond the ferrule 2. Snugly fitted to the outside of this tubular check seat I4 is a short tubular spring seat I9 the top of which abuts the lower sich of said iiange at top of check seat I4, and the bottom of which is formed. with an inward flangewhich is sprung into a peripheral recess 20 of the runner guide 6. Fastened to this bottom flange of the spring seat I 9 is the torsion spring 2| the lower end of which is secured to th'e lg 8 of the runner guide 6. This spring is not only in torsion but also in a state ofcompression greater than that of the spring I8 so as to keep the feed screw mechanism pressed up against the thrust washer I5.

Firuy holding this thrust washer, and with an easy running t, fitting over the barrel of the tubular spring seat I9 is the top bearing 22 which is formed with longitudinal depressions as shown (Fig. 3) to allow the passage of the spare leads, and then ls flared out to ilt firmly over the outside of the hexagon casing I (Fig.`1) Fitting over this bearing 22 suihciently snug. to be capable only of manual movement is .the eraser barrel 23. 'Ihis barrel extends up beyond the bearing 22 sufficient to allow to be retained ilrmly therein an eraser 24 and an eraser thrust seat 25. The center of this thrust seat 25 is formed down to fit loosely over the rectangular top of the check I1. (Figs. 1 and 4).

In Figure 1 the runner Ill is shown at the bottom of its stroke in the feed screw 9. Snugly pushed into the lower end of this tubular runner I0 is the short worn down tubular lead 26 ready to be pushed out of the runner I0 by the lead pusher I2 on further manual rotation of the feed screw 9 sufficient to bring the tits II and I3 at a distance apart equal to the lead of the feed screw.

From the foregoing construction explanation `it will be apparent that the operation of the pen- .of the feed screw 9 relative to the casing I and so, on account of the lug 8, also relative to the runner guide 6, will cause the runner I0 and lead pusher I2 to be retracted up into the pencil until they reach the upper end of their stroke. Further rotation of the eraser barrel in this direction simply causes the check I1 to rotate on the check seat Il. In this top position of the runner I0 a full length of a suitable writing element such as a tubular lead 28, or the like elongate piece of graphitic material having a longitudinally extending channel or bore in which the control rod I8 may be received, may be inserted to engage the lower end of runner I0 against the lead pusher I2. 'I'he writing end of the lead ther protrudes from the ferrule 2 at a distance approxii'nately flush or conterminous with the lowei end ofthe control rod I8. The pencil is then ready for writing. A

As, while writing, the lead wears down, the end of the control rod I8 is exposed to the writing pressure at the same time as the lead. This writing pressure against the control rod causes itto lift the check I1 from the seat I4 a very slight amount, sufllcient only to cause the check and seat to lose their frlctional engagement or grip, and thus allow the seat and the feed screw S to which it is fixed, to rotate in a right hand direction under the torsion force of the spring 2 I. This rotation of the feed screw 9 causes the runner I0 and lead pusher I2 to move down and feed down the lead. When the lead has moved down rsuilcient to remove the writing pressure from the end of the control rod the check I'I returns to lfrictional engagement. with the check seat Il and so stops the action of the said feed of the lead. This feed of the lead is only a few thousandths of an inch at a time; It will be noticed that the writing point of the lead is exposed to approximately the same distance ready for writing at all times and that the feed control does not impair or interfere with this writing point at any time, as shown more clearly in Fig. `5.

Now to draw attention to the writing point of the lead please observe the following feature. The lead is tubular so that, since the pencil is always held at an angle, as shown in Fig. 5, wear on the side of this tubular lead forms two sharp edges of a width equal to the thickness of the wall of the tube at the points of junction of the plane of the angle of wear and the plane of the end of the tubular lead. Either of these sharp edges may be continually used by rolling the pencil in the hand either one way or the other. It is partly due to this same fact that the pencil is always held at an angle while writing that the minute action of the feed is so smooth as not to be feit because the touch of pressure on the control tip comes after, as it were, the pressure on the side of the lead.

While I have shown and described one desirable embodiment of the present invention, it is understood that this disclosure is for the purpose of illustration only, and that various changes in shape, proportion, and arrangement of parts, as well as the substitution of equivalent elements for those herein shown and described, may be made without departing from the spirit and scope of the invention, as set forth in the following claims.

I hereby make the following claims:-

l. A writing device of the class described comprising a tubular body tapered at one end, a slotted guide within said body, a feed screw within said guide, aslidable pusher within said screw having offset portions engaging the thread of said screw and the slot of said guide, means urging said screw to rotate relative to said guide whereby to feed said pusher, a control element extending to a given point beyond the tapered end of said body, and means co-operating with said control element to control thereby the amount of relative rotation of said feed screw l with respect to said guide.

2. A writing device of the class described comprising a tubular body tapered at one end, a slotted guide within said body, a feed screw within said guide, a slidable pusher within said screw having offset portions engaging the thread of said screw and the slot of said guide, a torsion spring urging said feed screw to rotate relative to said guide whereby to feed said pusher toward tapered end of said body, a control element extending to'a given point beyond the tapered end of said body, and means zo-operating with said control element to control thereby the action of said spring in rotating the feed screw relative to said guide.

3. A writing device of the class described comprising atubular body tapered at one end, a slotted guide within said body, a feed screw within said guide, a slidable tubular pusher within said screw having offset portions engaging the thread of said screw and slot of said guide, and a torsion spring acting to urge said screwto rotate relative to said guide whereby to feed said pusher `toward tapered end of said body, an axial control element within said pusher but extending to a given point beyond the tapered end of said body, and means cooperating with'said control element to control thereby said action of said Spring.

4. A writing device of the class described comprising a tubular body tapered at one end and of said lead and having offset portions engaging the thread of said screw and the slot of said guide, a torsion spring having one end attached to said guide and its other end connected with the, top of said screw acting thus to urge said screw to rotate relative to said guide to actuate the pusher to push out said lead, an axial control element slidably disposed within said axial hole 4of said lead and having its lower end at a given distance beyond said tapered end of said body and its upper end urged into frictional engagement with top of said screw bya coin-i pression spring depending from top of said body,

a manually rotatable cap fitting over top of said body in slidable but non-rotatable connection with upper end of said control element.

5. A pencil comprising a tubular body having a writing element projecting from one end thereof, mechanism within saidvbody for feeding said writing element outwardly, and. control means associated with saidmechanism `for the end of said writing element at a predeter mined distance beyond the fend of said body, said control means including a kmember having an end conterminous with and disposed within the connues of the end of said writing element and arrangedconstantly to` Lengage the writing rsurface as the writing progresses.

6. A pencil comprising a tubular body having a writing element projecting from one end thereof, mechanism within said body for feedingl said writing element outwardly, and control meansoperative to effect the actuation of said mechanism so as to maintain the end of said writing elementk at a predetermined distance beyond the end of said body, said control means including a member having an end conterminous with and disposed within the wniines ofthe end of said writing element and arranged constantly to engage the writing surface as Athe writing-progresses.

7. A pencil comprising a tubular body having a writingelement projecting from one end thereof, mechanism within said body for feeding said writing element outwardly, and control means associated with said mechanism, includ- .ing a member which projects outwardly beyond said body with its end conterminous with and disposed within the connues of the end of saidl writing element and arranged constantly to en predetermined distance 8. A pencil comprising a tubular body having a writing element projecting from one end thereof, mechanism within said body for feeding said writing element outwardly, and control means including a member having an end conterminous with and disposed within the con'- nnes of the end of said writing element and arranged constantly to engage the writing surface as the writing progresses, said control means being operative in response to the wearing away of said writing element to eil'ect the actuation of said mechanismso as to maintain the end of said writing element at a predetermined distance beyond the end of said body.

9. A pencil comprising a tubular body having a writing element projecting from one end thereof, mechanism within said body for feeding said writing element outwardly, and control means comprising an outwardly projecting part conterminous with and disposed within the confines of the end of said writing elementand arranged constantly to engage the writing surface as the end of said writing element at a predetermined distance beyond the end of said body.

10. A pencil comprising a tubular body havin a lead projecting from one end thereof, said lead maintaining 3 having. a mammals extending enamel,

mechanism within said body for feeding said lead outwardly, and means associated with said mechanism comprising a control member dis posed in said channel and operative to effectthe actuation of saidmechanism so as to maintain the end of said lead at a predetermined distance beyond the end of said body.`

ll. A pencil comprising a tubular body having a lead projecting from one end thereof, said lead having a longitudinally extending'channel,

mechanism within said body for feeding said lead outwardly, and control means for maintaining the end of,` said lead at a predetermined distance beyond the end of said body, said means 4comprising amember disposed in said channel and normally projecting beyond the end of said body with its end conterminous with the end of said lead, said member being operative to spouse to the wearing away of the end of the lead. i

l2. A pencil comprising a tubular body having -n. lead projecting from one end thereof, said lead having a longitudinally extending channel, mechanism within said body for feeding said lead outwardly, and control means operative in respo'nse to the wearing away of said lead to effect the actuation of said m so as to maintain the end rof said lead at a predetermined distance beyond the end of said body, said means comprising an elongate member associated with said mechanism, said member being disposed'in said channel and projecting beyond the end oi' said body with its end conterminous with the point of the lead.

13. A pencil comprising a tubular body having a lead projecting from one end thereof, said lead having a longitudinally extending channel, mechanism within said body for feeding said lead outwardly, and control means for maintaining the end of said lead at a predetermined distance beyond the end of said bocLv, said means comprising a member disposed in said channel with its end conterminous with the end of said lead, said member being operative to eifect the actuation of said mechanism in response to pressure applied to its end.

14. In a pencil, the combination with a tubular body having a lead projecting outwardly from v one end thereof to permit writing, of mechanism for feeding said lead outwardly, and control` means comprising a member projecting outwardly beyond said body with its end conterminous with and disposed within the confines of the end of .said lead and arranged constantly to engage the writing surface as the writing progresses, said member being operative to effect the actuation of said mechanism to feed said lead outward ly and maintain its projecting end at a lprede-- termined distance beyond the end of said body.

l5 In a pencil, the combination with a tubular body having a lead projecting outwardly from one end vthereofto vpermit writing. said lead having a longitudinally extending channel, of mechanism ,for feeding said lead outwardly, and control means comprising an elongate member disposed n -in said channel and extending outwardly beyond s -said body with its end conterminous with the end of said lead, said member being operative to effect 16In a pencil, the combination with a tubular effect the actuation of said mechanism in re-v body having a tubular lead projecting outwardly from one end thereof to permit writing, of mechanism for feeding said lead outwardly. and control means comprising an elongate member disposed within said lead with its end conterminous with the end of said lead, said member being operative to effect the actuation lof said mechanism to feed said lead outwardly and maintain its projecting end at a predetermined distance beyond the end of said body.

17. A pencil comprising a tubular body having a tubular lead projecting from one end thereof, mechanism within said body for feeding said lead outwardly, and a control member having a part disposed within said lead with'its end conterminous with the end of said lead', saidmember being operative to control the operation of said mechanism in such a manner as to maintain the end of said lead at a predetermined distance beyond the end of said body.

18. A pencil comprising a tubular body having a tubular lead projecting from one end thereof, mechanism within said body for feeding said lead outwardly, and control means, including a part disposed within the bore of said lead, operative in response to the wearing away of said lead to effect the actuation of said mechanism so as to maintain the end of said lead at a predetermined f distance beyond the end of said body.

19. A pencil comprising a tubular body having a lead projecting from one end thereof, mechanism normally tending to feed said lead outwardly, check means normally counteracting the feeding movement of said mechanism, and a control member extending outwardly beyond said body with its end conterminous with and disposed within the confines of the end of said lead, said member being associated with said check means and operative to render said check means ineffective to counteract the feeding movement of said mechanism.

20. A pencil comprising a tubular body having a lead projecting from one end thereof, said lead having a longitudinally extending channel, mechanism normally tending to feed said lead outwardly, check means normally counteracting the feeding movement of said mechanism, and a control member disposed in said channel and extending outwardly beyond said body with its end conterminous with the end of said lead, said member being associated with said check means and operative to render said check means ineffective to counteract the feeding movement of said mechanism.

21. A pencil comprising a tubular body having a tubular lead projecting from one end thereof mechanism normally tending to feed said lead outwardly, check means normally counteracting the feeding movement of said mechanism, and a control rod disposed within said lead and extending outwardly beyond said body with its end conterminous with the end of said lead, said rod being associated with said check means and operative to render said check means ineffective to counteract the feeding movement of said mechanism.

22. A writing element for use with a pencil of the class described, said writing element comprising an elongate lead having an axial bore extending from one end to the other.

23. A writing element for use with a pencil of the class described, said Writing element comprising a cylindrical lead having an axial bore extending from one end to the other.

24. A writing element for use with a pencil of the class described, said writing element comprising a tubular piece of graphitic material.

FREDERIC R. BARKER. 

